Heterocyclic ketone condensates of acyclic succinic acids



United States 3.014,044 HETERGCYCLIC KETONE CQNDENSATES F ACYCLIC SUCCENIC ACEDS Donald Stalrer, Nitro, W. Va., assigncr to Monsanto Chemical Company, St. Louis, Mo., a corporation of Delaware N0 Drawing. Filed Aug. 15. 1957. Ser. No. 678,432 7 Claims. (Cl. 260-326.5)

The present invention relates to new compositions of matter and also to mineral oil compositions containing the new products. The compositions comprising the present invention are formed by the reaction, 'as later set forth in specific examples, of an alkyl or alkenyl suc- ClIllC acid or anhydride wherein the alkyl or alkenyl group contains from 8 to 15 carbon atoms with a heterocyclic keto compound,for example a lactam such as gamma-butyrolactam (Z-pyrrolidinone), gamma-valerolactam (-methyl-2-pyrrolidinone), N-methyl pyrrolidinone, Z-piperidone, 3-methyl 2-piperidone, 3-ethyl 2-pi- .peridone, 3-propyl Z-piperidone, oxindole and dioxindole, .or a lactone, as for example butyrolactone. The new compositions are oil soluble, particularly in petroleum ,oil fractions, and have been found to exhibit rust preventive properties towards metals, especially steel and .ferrous iron surfaces. The simplest and most convenient method of developing a rust preventing film on a metal surface is to dissolve one of the preferred class of rust preventive compounds disclosed herein in a suitable petroleurn base carrier such as a motor gasoline, aviat'on .gasoline, jet fuel, turbine oil and the like. Inasmuch as the lead saltsof compounds of the herein preferred class of compounds do not form, or if formed are complete'y soluble in the petroleum fraction employed, the compounds hereinafter described may be used in tetraethyl .lead treated fuels. Moreover, the alkaline earth salts of the preferred class of compounds either do not form when contacted with sea water or are soluble in hydrocarbons, thereby permitting theme of sea Water ballast in storage .tanks earlier loaded with an oil fraction or fuel treated with one of the preferred rust preventive compounds.

Since the structure of the new compounds is not known with certainty, they can be described only as reaction 'products but the invention can be readily understood from the description that follows as examples of the formation 'of the compounds and their use as rust preventives.

EXAMPLE l-PRODUCT A -Into avessel provided with a stirrer, condenser and temperature recording means, there were added 131.5 parts of dodecenyl succinic anhydride and 42.5 parts of 2-pyrrolidinone (gamma-butyrolactam). The anhydride was obtained from propylene polymer and maleic anhydride and may also be called tetrapropenyl succinic anhydride. The agitated mixture was then heated between 1101l6 C. for a period of several hours and the neutralization number determined from time to time on samples withdrawn from the reaction. Since there was no change in this value for a 5 hour period, the heaing ber of 320 is the calculated value for the mixed anhydride amide which would be formed by splitting the 2-pyrrolidinone ring between the nitrogen and the carbonyl, the nitrogen forming an amide and the carbonyl reforming an anhydride linkage by uniting with the acid radicalr 3,014,044 Patented Dec. 19, 1961 stances.

EXAMPLE 2-PRODUCT B Into the same type equipment employed in Example 1, there were added 131.5 parts (0.5 mole) of dodecenyl succinic anhydride, 9 parts (0.5 mole) of water and 49. 6 parts (0.5 mole) of N-rnethyl Z-pyrrolidinone. The agitated mixture was heated at 98-l02 C. and samples withdrawn from time to time and tested to determine the neutralization number. Titration with alcoholic caustic potash should develop a value of 290 for complete reaction. Heating of the mixture was discontinued after 10 /3 hours since the neutralization number appeared to be constant at 278. The product of the reaction was completely soluble in petroleum ether.

EXAMPLE 3-PRODUCT C EXAMPLE 4-PRODUCT D stant, heating was discontinued. The product was com- .pletely soluble at 5% concentration in petroleum ether.

EXAMPLE 5-PRODUCT E Into the same type equipment employed in Example 1 was charged 133 parts of dodecenyl succinic anhydride, 43 parts of butyrolactone and 9 parts of water. The charge was heated at 97-l00 C. for about 13 hours at which time the neutralization number was 302 and the product completely soluble in petroleum ether at 5% concentration.

The application of the products of the present invention as rust inhibitors was determined by a series of tests. The various products were tested to determine their solubility in petroleum oil by adding 1% by weight of the reaction product to 100 parts by weight of petroleum ether and stirring. If any residue be observed, the product is indicated as insoluble. The rust preventive properties of the chemical products were observed by carefully cleaning and polishing, in the well recognized manner for performing this test, strips of steel 3 /2" x x V having an S.A.E. grade designation of 1020 and vigorously shaking each specimen in cc. of petroleum ether containing the desired concentration or concentrations (from 5 to 20 parts per million of solvent) of the rust inhibitor. After standing for one-half hour, 2 cc. of distilled water were added and the sample re- Qshaken. The strip was allowed to stand in the wet petroleum ether at room temperature for about 3 hours and was then removed and visually inspected for rust. The

results of the tests with typical members of the new class of reaction products are set forth in the following table:

a 4 Table I Table II Solubility in Steel Strip Rust Test Solubility Sea Water Lend Product Petroleum in Petro- Water Toler- Salt Ether r Product ileum Rust Test (ilcsti (gIcstl 20 .m .m. 5 .m. 0 ther nso cs use p p p p p p uhlcs) ubles) complete.-. slight.

. none. A complete... pass at ppm... trace pass" none. trace. B -.do ..do none. ..do. Do. rust. fail..- do. Do. none. l0. Do.

Iai1..- -..do... Do.

Various other tests utilized in the art were also employed in the further testing of chemical products of the present invention. A description of such tests and the results obtained therefrom follow.

Water tolerance test, A.S.T.M. 109453.-This test is used to evaluate the emulsion characteristics of the rust inhibited petroleum fraction, such as a petroleum fuel. The apparatus consists of a 100 cc. glass stoppered graduated cylinder, which after thorough cleaning is rinsed thoroughly with distilled water and stored completely full of distilled water until used in a test. The water is removed and 80 cc. of iso-octane containing 20 parts per million of the inhibitor under test is placed in the graduate and 20 cc. of distilled water added thereto and the mixture is shaken vigorously at room temperature for 2 minutes. The mixture is then allowed to stand on a vibration-free surface for 5 minutes whereupon the volume of the aqueous layer and the amount of emulsion, if any, are recorded. In order to pass the test, the fuel shall separate sharply from the water and there shall be no evidence of an emulsion, precipitate or suspended matter within or upon either layer. Neither layer shall have changed more than 1 cc. in volume.

Sea water reaction tes. .-This test is designed to determine the solubility of the alkaline earth salts of rust inhibitors. Synthetic sea water was prepared according to the method set forth in Procedure B, A.S.T.M. D665- 531. The method consists in adding 250 cc. of n-heptane containing about 200 ppm. of the material to be tested and cc. of synthetic sea water to a 500 cc. S-neck flask equipped with stirrer and reflux. condenser and stirring for minutes at room temperature. Agitation was stopped and when motion had ceased the interface was examined for scume and the walls of the fiask examined for precipitate of which there shall be none.

Lead salt test-This test is designed to indicate the possibility of precipitate from the use of rust inhibitor in a leaded gasoline. In this test, an ionizable leadsalt is added to assure a concentration of lead ion. The test solution is prepared by dissolving 25 parts of lead naphthenate in 2500 parts of a regular gasoline and the solution is filtered through a double thickness of filter paper and then through a layer of fullers earth. Thereupon 100 cc. of the test solution is added to a 500 cc. 3-neclt flask equipped with a stirrer and air condenser. Agitation is started and the rust inhibitor under test is added dropwise until about 0.5 gram has been added whereupon agitation is continued for an hour at room temperature and the mixture is examined for haziness or insolubles with the aid of a flashlight. To pass the test there shall be no more haze than is exhibited by use of a blank test with no inhibitor present.

The rust preventing characteristics of a steam turbine oil containing a product of the present invention in the presence of water was determined by following A.S.T.M. Test D665-53T, Procedure B thereof. The oil employed was a base stock in commercial use for the formulating of steam turbine finished lubricants and, of course, contained no inhibitor of any kind. In this test and the other tests described above, various reaction products of an alkenyl succinic anhydride yielded the results shown below in Table II.

The results of the several tests clearly show that the new reaction products of the class described are oil soluble, are effective in protecting ferrous iron and steel against rusting in oil-water contact and do not form continuous oil-water emulsions.

It is intended to cover all changes and modifications of the examples of the invention chosen for purposes of disclosure which do not constitute departures from the spirit and scope of the invention.

What is claimed is:

1. A petroleum ether soluble rust inhibitor titratable with potassium hydroxide obtained by heating at -120" C. a heterocyclic ketone selected from the group consisting of 2-pyrrolidinone, 5-methyl-2-pyrrolidinone, N- methylpyrrclidinone, 2-piperidone, 3-rnethyl-2-piperidone, 3-ethyl-2-piperidone, 3-propyl-2-piperidone, oxindole, dioxindole and butyrolactone with a member of the group consisting of alkenyl succinic anhydride and alkenyl succinic acid containing 8-15 carbon atoms in the alkenyl radical.

2. A petroleum ether soluble rust inhibitor titratable with potassium hydroxide obtained by heating at 95-120 C. a heterocyclic ketone selected from the group consisting of 2-pyrrolidinone, 5-methyl-2-pyrrolidinone, N- methylpyrrolidinone, 2-piperidone, 3-methyl-2-piperidone, 3-ethyl-2-piperidone, 3-propyl-2-piperidone, oxindole, dioxindole and butyrolactone with alkenyl succinic anhydride containing 8-15 carbon atoms in the alkenyl radical.

3. A petroleum ether soluble rust inhibitor titratable with potassium hydroxide obtained by heating at 95-120 C. N-methyl-Z-pyrrolidinone and branched chain dodecenyl succinic acid.

4. A petroleum ether soluble rust inhibitor titratable with potassium hydroxide obtained by heating at 95-120 C. 2-pyrrolidinone and branched chain dodecenyl succinic anhydride.

5. A petroleum ether soluble rust inhibitor titratable with potassium hydroxide obtained by heating at 95-120 C. 2-pyrrolidinone and branched chain dodecenyl succinic acid.

6. A petroleum ether soluble rust inhibitor titratable with potassium hydroxide obtained by heating at 95120 C. butyrolactone and branched chain dodecenyl succinic acid.

7. A petroleum ether soluble rust inhibitor titratablc with potassium hydroxide obtained by heating at 95-120 C. butyrolactone and branched chain dodecenyl succinic anhydride.

References Cited in the file of this patent UNITED STATES PATENTS 1,908,705 Jaeger May 16, 1933 1,941,689 Jaeger Jan. 2, 1934 2,303,177 Schlack Nov. 24, 1942 2,458,425 Rocchini Jan. 4, 1949 2,625,511 Rocchini Ian. 13, 1953 2,682,526 Flory June 29, 1954 2,698,845 Mastin et al. J an. 4, 1955 OTHER REFERENCES Shpitalnyi et al., Chem. Abs., 47, 341 (1953). 

1. A PETROLEUM ETHER SOLUBLE RUST INHIBITOR TITRATABLE WITH POTASSIUM HYDROXIDE OBTAINED BY HEATING AT 95-120* C. A HETEROCYCLIC KETONE SELECTED FROM THE GROUP CONSISTING OF 2-PYRROLIDINONE, 5-METHYL-2-PYRROLIDINONE, NMETHYLPYRROLIDINONE, 2-PIPERIDONE, 3-METHYL-2-PIPERIDONE, 3-ETHYL-2-PIPERIDONE, 3-PROPYL-2-PIPERIDONE, OXINDOLE, DIOXINDOLE AND BUTYROLACTONE WITH A MEMBER OF THE GROUP CONSISTING OF ALKENYL SUCCINIC ANHYDRIDE AND ALKENYL SUCCINIC ACID CONTAINING 8-15 CARBON ATOMS IN THE ALKENYL RADICAL. 